Electro-optical and lasing properties of hybrid quantum dot/quantum well material system for reconfigurable photonic devices

Abstract

We characterize the electro-optical and lasing properties of a hybrid material consisting of multiple InAs quantum dot (QD) layers together with an InGaAs quantum well (QW) grown on a GaAs substrate. Over 40 nm Stark shift of the InGaAs QW leading to 9 dB extinction ratio was demonstrated. Lasing operation at the QD first excited state transition of 1070 nm was achieved and together with < 10 ps absorption recovery the system shows promise for high-speed mode-locked lasers and electro-modulated lasers. (C) 2013 American Institute of Physics. (http://dx.doi.org/10.1063/1.4791565

On the origin of carrier localization in AlInAsSb digital alloy

“…The lowtemperature activation energy E 2 is likely to originate from a local state associated with the roughness of the interface as the E 2 values (6.72 meV and 3.76 meV) for both samples are comparable to the exciton binding energy in several quantum structure systems. [12,34,35] Figure 2 reveals that sample B has better crystal quality, suggesting that increasing the thickness of the interfacial layer generates a more uniform interface and reduces interfacial roughness. Furthermore, InSb-like interfaces have been proven to exhibit smoother interfacial and fewer point defects than AlAs-like interfaces in InAs/AlSb quantum wells and superlattices.…”

“…34.32 meV (41.71 meV) is the thermal activation energy for the high-temperature range of 80 K-255 K (105 K-278 K).…”